Failing Fast

Fail-fast or cancelling runs on first failure

Automatically cancelling your test suite right after the first failure is called a "fail-fast strategy". Currents dashboard allows tracking the outcome of your tests and automatically cancels runs whenever the first failed spec file is detected.

After executing a spec file, the runner sends the results to the Currents dashboard. The dashboard receives the results, identifies a failed test, and marks the associated run as "cancelled". Any new requests associated with the run will fail with a warning, as a result, cypress runners will not be able to start executing a new spec file for the run.

Please note, that any spec file that is still in progress will run to completion and its results will still be accepted.

Example of a run automatically cancelled via "fail-fast" policy

Using a "fail-fast" strategy can be beneficial because:

• it reduces CI resources usage by preventing running additional tests after detecting just a single failure;

• potentially getting faster feedback for runs with a failed test - you don't need to wait for the run to finish;

• it reduces the number of tests results recorded on the Currents dashboard;

• it prevents Run Timeouts when an external tool (CI or a script) terminates cypress tests prematurely.

At the same time, utilizing a "fail-fast" strategy has some caveats:

• not all the tests will be executed - you will only see the results of a single test - the first test that triggered the "fail-fast" policy;

• tackling one failure at a time can result in more runs than necessary - one can invest more time and resources, compared to running all the tests regardless of their results.

Automatically cancelled runs will be marked as failed and cancelled

If you are dealing with a stable and predictable suite of tests that rarely fail - "fail-fast" can be a great way to optimize your cypress tests.

Read more about how cancelling runs affects runs status, analytics and integrations

Enabling fail-fast strategy

To enable the "fail-fast" strategy navigate to the Manage Project screen and toggle Enable Fail Fast Strategy controller.

Customers using our cypress-cloud integration can control the "fail-fast" behaviour using the command line CLI flag --auto-cancel-after-failures <number | false>.

Customers using our @currents/playwright integration can use --pwc-cancel-after-failures <number | false> option.

If set, it overrides the project's default fail-fast strategy setting. If not set, use the default project settings:

• false prevents fail-fast

• number aborts the run across all the participating machines failed + skipped tests detected exceed the provided value

For example

• npx pwc --key xxx --project-id xxx --ci-build-id id-001 --pwc-cancel-after-failures 1

• npx cypress-cloud run --parallel --record --key xxx --ci-build-id id-001 --spec "./cypress/e2e/*.spec.js" --auto-cancel-after-failuresfalse will deactivate the fail-fast strategy, regardless of your project settings

• npx cypress-cloud run --parallel --record --key xxx --ci-build-id id-001 --spec "./cypress/e2e/*.spec.js" --auto-cancel-after-failures5 will stop the run if more than 5 failed tests detected